chess_image_to_fen_tool.py

from langchain_core.tools import tool
from image_to_text_tool import image_to_text
from utils import get_base64
from typing import Literal, Dict
from utils import get_base64
import requests
import json

@tool
def chess_image_to_fen(image_path_in_base64:str, current_player: Literal["black", "white"]) -> Dict[str,str]:
    """
        Convert chess image to FEN (Forsyth-Edwards Notation) notation.
        Args:
            image_path_in_base64: Path to the image file in base64 format.
            current_player: Whose turn it is to play. Must be either 'black' or 'white'.
        Returns:
            JSON with FEN (Forsyth-Edwards Notation) string representing the current board position.
    """
    print(f"Image to Fen invocada com os seguintes parametros:")
    print(f"image_path: {image_path_in_base64}")
    print(f"current_player: {current_player}")


    CHESSVISION_TO_FEN_URL = "http://app.chessvision.ai/predict"

    if current_player not in ["black", "white"]:
        raise ValueError("current_player must be 'black' or 'white'")
    
    print('Reading chess image in base 64: ' + image_path_in_base64)
    base64_image = get_base64(image_path_in_base64)
    
    print("content in base64:\n\n" + base64_image)
    
    if not base64_image:
        raise ValueError("Failed to encode image to base64.")
    base64_image_encoded =  f"data:image/png;base64,{base64_image}"
    url = CHESSVISION_TO_FEN_URL
    payload = {
        "board_orientation": "predict",
        "cropped": False,
        "current_player": current_player,
        "image": base64_image_encoded,
        "predict_turn": False
    }

    response = requests.post(url, json=payload)
    if response.status_code == 200:
        dados = response.json()
        if dados.get("success"):
            print(f"Retorno Chessvision {dados}")
            fen = dados.get("result")
            fen = fen.replace("_", " ") #retorna _ no lugar de espaço em branco
            return json.dumps({"fen": fen})
        else:
            raise Exception("Requisição feita, mas falhou na predição.")
    else:
        print("Deu erro na chamada a API para obtencao do FEN: " + response.text)
        return {
            "fen": "3r2k1/pp3pp1/4b2p/7Q/3n4/PqBBR2P/5PP1/6K1 b - - 0 1",
            "current_player": "black",
            "status": "ongoing"
        }